Tank-car-dome cover



M. A. GARRETT.

Patented Feb. 7, 1922.

2 SHEETS-SHEET I.

M. A. GARRETT.

TANK CAR DOME COVER. APPLICATION FILED SEPT. 16, I920.

1,405,577. Patented Feb. 7, 1922 2 SHEETS-SHEET 2.

- tion.

UNITED STATES PATENT e ca MYERS a emu, or cinca'oo, ILLINOIS, ASSIGNORor ONE-BALI To cm'ron 1). runs AND ONE-EAL]? r0 CARLTON M. GARRETT,Born: or zmw Yoax, N. Y.

TANK-CAR-DOME covan.

Specification of Letters Patent.

Application filed September 10, 1920. Serial No. 416,808.

To all whom it may concern:

Be it known that I, MYERS A. GARRETT, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Tank-Car-Dome Covers;and I do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

Most of the dome covers on tank cars now in use are very faulty indesign and construc- They are heavy and cumbersome to handle and arescrewed in position so that it is difiicult to get them down tight, andthe result is a very great loss of the loading when volatile as in thecase of gasoline. Vapor arises into the dome space, and the pressure ofit is so great at times that when the screw cover is being'removedfrequent and serious accidents occur to the persons manipulating thecovers by reason of the cover being blown off before being entirelyunscrewed. Besides, there is great loss of the loading of the carinasmuch as the sudden removal of the cover when gas pressure is presentthrows the loading out of the dome opening. The action is similar to theopening of a bottle of champagne. Because of the Weight of the cover,the screwing of it down frequently damages the threads and displaces thegaskets when used to make a tight joint. Even though the cover isscrewed down tight, vents or openings are present, due to the defectivegaskets and damaged threads. From the foregoing, it is obvious that thecover should be provided with a vent or vents to reduce the gas pressurebefore loosening the cover, and the arrangement should be such that itwill not be possible to move the cover away from the dome opening untilthe gas pressure within the dome is reduced or entirely removed.

"""While the screw type of cover has vents in the threaded part of thesame which are designed to relieve the gas ressure, nevertheless thereis no control o the movement of the cover to forestall possibleaccidents and loss of loading before the pressure is suflicientlyreduced. Men generally will be careless in dangerous situations andtherefore a mechanical control is necessary to prevent accidents.

My im roved dome cover obviates the imperfections of. the type now inuse. It

allows the escape of gas gradually so there 1s no dangerous rush thereofwhichattends a sudden full opening of the vents, or theremoval of thecover. It is notscrewed in closed position, but is hinged so that it canswing upwardly and back, thus not disturbingor damaging the gasket byfrictional circular movement. It is made tight by hinged bolts with nutswhich can be. readily screwed down tight with an ordinary wrench. Thecover being hinged, it can be operated easily as compared with the screwtype of cover, and further it cannot be displaced and lost. Some of thenuts of the hinged bolts which clamp the cover in 'osition can not beloosened until the excessive gas pressure has been reduced.

The accompanying drawings illustrate two examples of the embodiment ofmy inventlon, one adapted for new cars being manufactured, and the otherfor old cars wherein my improvement is substituted, the same beingconstructed and the parts combined accordingto the best modes ofprocedure I have so far devised for the purpose.

Figures 1 and 2, the former a top plan view and the latter a verticalsection on llne 2-2 of Fig. 1, show the first example which is to beembodied in new tank car construction.

Figures 3 and 4, the former a top plan view and the latter a verticalsection of Fig. 3 on line 44, show the second example where the newcover is adapted for old cars re lacing the screw type or cover.

igure 5 is a cross section enlargement of. the hollow plug taken on line5-5 of Fig. 2.

eferring to the first example, Figs. 1, 2 and 5, the numeral 1designates the tank car metallic dome head sheet having a circularopening 2. About the edge of the metal defining the opening is securedby rivets 3 a ring 4, having a bottom flange 5, through which the rivets3 pass, and a flange 6, provided with a plurality of open slots 7 in theedge. Within these slots are located a plurality of threaded bolts 8which are pivoted at their lower ends by through bolts 9 to perforatedpairs of lugs 10 cast integral Patented Feb. 7, 1922. i

with the ring 4, as shown. .Projecting from a hinge. The holes in thelugs 11 are elongated or elliptical vertically so the bolt can movevertically and allow the cover to closely fit the top surface of theflange 6, as is obvious.

The cover 14 has open slots 16 in its edge.

which re ister with'the slots 7 in the flange 6, where y the boltswithin the said slots, when the nuts 17 are unscrewed, can be turnedoutwardly to horizontal positions freeing the cover so it can be swungupwardly upon its hinges. Within a recess formed in the under surface ofthe cover is located a circular gasket 18, which is adapted to engagethe top surface of the flange 6 and form an air tight joint.

At the center of the cover is a threaded opening 19, within which islocated a removable threaded plug 20. The lower part of the plu ishollow and has top and bottom holes 21 t rough it in differenthorizontal planes, as shown by Figure 5. A rivet 22 with projectingheads prevents the plug from being entirely removed from the cover andlost. Upon the plug above the screw threads is a fixed collar 23, andspaced therefrom and above the. collar is a nut 24 having a flange witha series of open perforations 25, as shown.

The nut is secured upon the upper end of the lug by a rivet 26 havingcountersunk head so as not to interfere'with the fit of a wrench.Between the collar 23 and the nut 24 is loosely pivoted, so it can turnabout the hollow plug a nut guard 27 provided with a plurality of radialarms 28, each arm at the end having a slot or recess within which islocated one of the nuts 17. The arms are united by curved bars 29, asshown, and one arm is provided with a perforated lug 30, through whichperforation and one of the holes 25 in .the flange of the nut 24 may bepassed a wire whenthe nut is to be sealed against unauthorized movementor removal. If desired, through rivets 31, with project-- ing heads, maybe added to the ends of bolts 17 so the nuts cannot be entirelyunscrewed and lost. On the inner'surface of the cover and projectingdownwardly is .a lug '32 which is so located as to serve as a lock toprevent movement of the valve rod operating lever, whether of thevertical or horizontal type, when the cover is closed.

The second example of the embodiment of the invention, Figs. 3 and 4,which is designed to be substituted for the dome covers of old tank carsnow in use differs from the example described mainly in the means forsecuring the ring, against which the cover bears, to the dome head sheet1, which has a circular opening. About the opening in the dome headsheet is secured by rivets A, a circular casting B, havin a lane surfaceC, and a threaded ed lhis ring may have been in use on o (1 cars toreceive the screw-threaded type 0f cover hereinbefore mentioned. Acircular ring E, having screw threads F, a flange G, with a gasket H andplain edge I, is screwed into thecircular casting B until the engagesthe plain surface of the casting and forms. a permanent tight joint. Theedge of the flange G may have a series of recesses J in its edge toreceive a suitable tool for use in screwing the ring E in place.

The cover and its attachments are substantially identical with the coverof the first example, and the description of the same need not berepeated. However, it will be noted that the gasket 18 fits the plainedge I of the ring E, and that the flange G carries the two perforatedlugs 11,

forming part of the cover hinge, the flange being widened as indicatedto properly locate the lugs. It will be obvious that the casting B andthe circular ring E, having screwthreads F and permanently screwed intothe said casting B forms a compound or composite ring which is rivetedto the body sheet of the tank car, and that said composite ring isbroadly the equivalent of the ring 4 of the first example.

The mode of operation is as follows: As-

suming the cover in either example to be closed as shown by thedrawings, it will be noted that it fits tightly and has no openings.

through which gas or liquid can escape. The nut guard revents theapplication of a wrench to a p urality of the nuts 17, and when a sealis present, the plug 20 cannot be turned without breaking the seal. Toopen the cover a wrench is applied to the nut 24 and the same unscrewedfrom the cover. When the top edges of the top holes 21 in the plug arebrought to a position slightly above the top surface of the cover, gasunder pressure within the dome can gradually escape until the pressureis sufliciently reduced inside the dome and car. It will be observedthat the threads upon the plug 20 are limited in area so as entirely toengage the threads about the hole 19 in the-center of the cover onlywhen the plug is screwed down and the collar 23 engages the top surfaceof the cover. The design is that when the plug has been unscrewed andthe threads thereon entirely freed from the threads in the cover, theends of the arms of the nut guard will be raised above the ends of thebolts 8 far enough to permit the use of a wrench to unscrew the nuts 17so the bolts 8 may beturned down to horizontal positions and out of theslots,

thus allowing the cover to swing upwardly;

conditions hereinbefore set forth and elimitype of cover now in use. Thecover can be easily and quickly manipulated and it cannot be lost. Avery tight joint is formed without openings through which gas or theliquid contents of the car can. escape. The gaskets will not be injuredin manipulating the cover. The nuts on some of the bolts cannot beunscrewed till the central plug has been unscrewed. Provision is madefor allowing the gradual reduction of gas pressure within the dome andcar before the cover is at all loosened from its seat. And, moreover,the improved cover is adapted for application not only to new cars, butalso to replace covers now in use.

What I claim is:

1. The combination with a tank body sheet having an opening, of a ringsecured about said opening and provided with threads; a second ringhaving threads to match the threads of the first-mentioned ring, aflange and an edge to receive a cover,

first-mentioned ring has a plain surfaceagainst which the flange of thesecond-mentioned ring bears when said rings are screwed together.

-3. The subject-matter of claim 1, when the first-mentioned ring has aplain surface and there is interposed between said surface and theflange of the second-mentioned ring a gasket forming a tight joint whensaid rings are united.

4. The combination with atank body sheet having an opening, of a ringsecured about said opening and provided at its edge with a seat to beengaged by a cover, hinged threaded bolt shanks pivotally secured to thesaid ring, a cover having slots at its edge to receive the said boltshanks, nuts upon the bolt shanks for forcing the cover into closefrictional contact with the edge of the ring, and means movable relativeto the cover for guarding a plurality of the nuts upon the bolt shanksso they cannot be unscrewed until the said means is removed.

5. A cover for a tank car 0 ening having a threaded hole with a threadedscrew-plug therein and a passage through the plug, the top openingthereof being located below the top thread of the plug and the loweropen- -ing 1n communication with the interior of'- the tank, wherebywhen the plug is unscrewed the top opening to the passage is broughtinto communication with the atmosphere and a discharge vent provided forthe escape of gas.

6. A cover for an opening in a tank car having a threaded holetherethrough, and a threaded plug adapted to fit the hole, the lowerpart of the plug being hollow and open to the interior of the tank carand the hole through the threaded part of the plug in communication withthe interior of the plug, for the purpose set forth. 7 7. Thecombination with a tank body sheet having an opening, of a ring securedabout said opening and provided at its edge with a seat for a removablecover, a cover detachably secured to the ring by bolts and nuts, athreaded hole in the cover, a threaded plug in said hole, and a nutguard device in connection with the plug and adapted to be raised andlowered along with the plug when it is screwed into and out of the holein the cover.

8. The subject-matter of claim 7, when the said plug is provided with acollar and a nut, between which a part of the nut guard is located.

9. The subject-matter of claim 7, when the said plug is provided with apassage thereth rough which 'opens' communication between the interiorof the tank car and the atmosphere only when the plug is partiallyunscrewed and when entirely unscrewed raises the guard above the nuts onthe bolts.

10. The combination with a. tank body sheet having an opening, of acasting provided with a flange and screw-threads, a ring having a seatfor a cover and threads, said ring being screwed into said casting andthe casting riveted to the tank body sheet through the flange and aboutthe opening, and a detachable cover matching the seat on said ring.

' 11. The subject-matter of claim 10, when said ring is provided with aflange which engages the said casting.

12. The subject-matter of claim 10, when the cover is provided with agasket which engages the top ed e of the said ring and the cover issecure to said ring by bolts and nuts.

13. The combination with a tank car having an opening with a seat for acover, the cover having a threaded hole, of a threaded plug. bolts andnuts detachably securing the cover in position, and a nut guard providedwith arms having slots within which the nuts are located when the coveris in position, said guard being connected to the said plu 14. Thecombination with a tank car cover secured in position by bolts and nuts,said cover having a central threaded hole. of a threaded lug fitting thehole, and a nut guard with a central opening loosely mounted upon theplug and adapted to be raised and lowered therewith.

In testimony whereof I aflix my signature.

. MYERS A. GARRETT.

